Hentai (変態 or へんたい) is a term in the English-speaking world that generally encompasses all Japanese adult anime and manga pornography, containing sexually explicit images and plots. It is derived from the Japanese term hentai seiyoku, meaning a perverse sexual desire.
Hentai consists of many subgenres, several of which feature in the Bible Black series. Examples include futanari (hermaphroditism), shokushu goukan (tentacle erotica) and yuri (lesbianism).
- HentaiWP on Wikipedia.